Data/hora: 13/06/2024 22:02:44

Provedor de dados: | 19
País: | Japan

Título:

十勝地域の未耕地土壌および農耕地土壌におけるリン酸の垂直分布と蓄積量

Vertical distribution and accumulation of phosphate in virgin soils and arable soils of Tokachi district，Hokkaido

Autores: | 谷, 昌幸; 溝田, 千尋; 八木, 哲生; 加藤, 拓; 小池, 正徳; TANI, Masayuki; MIZOTA, Chihiro; YAGl, Tetsuo; KATO, Taku; KOIKE, Masanori.
Data: | 2010
Ano: | 2010
Palavras-chave: | リン酸蓄積; 黒ボク土; 褐色低地土; 層厚差; 垂直分布; Andosols; Brown Lowland soils; Soil thickness; Phosphate accumulation; Vertical distribution.
Resumo: | 本研究では，十勝地域の農耕地，とくに普通畑土壌にお ける肥培管理などが土壌へのリン酸蓄積量とその形態に及ぼす影響を明らかにすることを目的とした.畑地およひ隣接する未耕地において土壌断面調査と試料採取を行い，土壌中の全リン酸含量および各種形態別リン酸含量の垂直分布を調べたさらに，仮比重および未耕地と農耕地における土壌の層厚差を考慮し正味のリン酸蓄積量を調べた. 1)淡色黒ボク土，厚層黒ポク土，および普通褐色低地 土のいずれの農耕地土壌においても，施肥などに由来する余剰リン酸は耕起の影響を受けた表層30~40cm までの 作土層に蓄積し，物理的に撹拌および混和されることにより作土層全体に比較的均一に分布した. 2)未耕地土壌との垂直分布の比較から，黒ボク土では 余剰リン酸が下層へ溶脱せず作土層にのみ蓄積し，褐色低地土では一部が下層へ溶脱していると考えられた. 3) 農耕地における正味のリン酸蓄積量は，黒ボク土で 著しく多く，年平均130kgha-1以上であった. 大部分は，フッ化物イオンの配位子交換能により抽出され，活性アルミニウムなどに特異吸着されていると考えられた褐色低地土では蓄積量が少なく，弱酸可溶のリン酸水素カルシウムや，弱い配位子交換反応で抽出可能な非品質リン酸アルミニウムなどの沈殿として蓄積していると考えられた.Heavy application of phosphate fertilizer and subsequent phosphate accumulation in arable soilsï¼ especially Andosolsï¼ are critical issues for sustainable agriculture in ]apan. The effects of fertilization and plant nutrient management on phosphate accumulation and its speciation in uncultivated virgin soils and cultivated upland so1is of Tokachi districtï¼ Hokkaidoï¼ were investigated. Three pairs of virgin and arable soi1 profiles were collected from adjacent sites to evaluate the vertical distribution of totalï¼ se quentially extractableï¼ and available phosphates in the soils. Net accumulated amounts of phosphate in the arable soi1s were ca1culated whi1e accounting for bulk density and differences in the thickness of layers between upland and adjacent virgin soils. In soils classified as Low-humic Andosols (Typic Hapludands)ï¼ Cumulic Andosols (Pachic Melanudands)ï¼ and Haplic Brown Lowland soils (Fluventic Dystrudepts)ï¼ surplus phosphates were accumulated at depths of 0-40ï¼ 0-30ï¼ and 0-35 cmï¼ respectivelyï¼ of the arable soil proliles. Phosphates were distributed homogeneously in the plow layer due to physical disturbance and mixing. The vertical distributions of phosphate in the paired virgin and arable soils indicated that most of the surplus phosphate accumulated without leaching in the plow layer of the Andosolsï¼ whereas some surplus phosphate leached out from the surface layer of the Brown Lowland soils. Net accumulated amounts 01 phosphate in the cultivated Andosols were remarkably largeï¼ with estimated annual accumulation rates of &gt;130 kg ha-1. Most of the accumulated phosphate may be specilically adsorbed by active aluminum and ironï¼ which could be extracted by fluoride through a strong ligand-exchange reaction. The net accumulated phosphate in the cultivated Lowland soil was relatively small. Most of the phosphate may accumulate through precipitation processes as calcium hydrogen phosphate and amorphous aluminum phosphateï¼ which could be dissolved by weak acids and extracted by a weak ligand-exchange reactionï¼ respectively.
Idioma: | Japonês
Identificador: | http://ir.obihiro.ac.jp/dspace/handle/10322/2696
Editor: | 日本土壌肥料学会
Formato: | application/pdf
Fonte: | 日本土壌肥料学会